A heat exchanger, such as an air conditioner, is typically constructed by stacking a plurality of heat exchanger fins, in which a plurality of through-holes is drilled to enable heat exchanger tubes to be inserted.
Such heat exchanger fins are manufactured by a manufacturing apparatus for heat exchanger fins illustrated in FIG. 7.
The manufacturing apparatus for heat exchanger fins is equipped with an uncoiler 12 where a thin metal plate (metal strip) 10 made of aluminum or the like has been wound into a coil. The metal strip 10 pulled out from the uncoiler 12 via pinch rollers 14 is inserted into an oil applying apparatus 16 where machining oil is applied onto the surface of the metal strip 10, and is then supplied to a mold 20 provided inside a press apparatus 18.
The mold 20 internally includes an upper mold die set 22 capable of up-down movement and a lower mold die set 24 that is static. In the metal strip 10 having passed through this mold 20, a plurality of collar-equipped through-holes 15 (also referred to simply as through-holes in the present specification in some cases), where collars of a predetermined height are formed around the drilled through-holes, are formed at predetermined intervals in a predetermined direction.
Such metal strip 10 is, after being conveyed in a predetermined direction for a predetermined distance, cut into a predetermined length by a cutter 26 and then accommodated in a stacker 28.
In a press apparatus 18, a feeding apparatus 31 that intermittently conveys the metal strip 10 in which the plurality of through-holes 15 is formed at the predetermined intervals in the predetermined direction is provided in a direction of a cutter 26.
As illustrated in FIG. 8, the feeding apparatus 31 conveys the metal strip 10 in the conveying direction by causing a feeding pin 29 to enter the through-hole 15 formed in the metal strip 10 from below and moving the feeding pin 29 in the conveying direction.
As illustrated in FIG. 9, when the metal strip 10 has been conveyed to a predetermined position, the feeding pin 29 is lowered and removed from the inside of the through-hole 15. Then, the feeding pin 29 moves in a direction opposite to the conveying direction (return direction) so as to return to an initial position while keeping a position not in contact with the metal strip 10.